This invention relates generally to protective coverings for wounds, blisters and the like, or as a preventive covering in areas of the skin where blisters tend to form, to prevent blisters from forming. It relates especially to a blister bandage that has high oxygen permeability, but is a liquid barrier, is flexible, strong, and a bacteria barrier. Today, bandages and wound dressings consist of many different forms. One bandage such as that made by Johnson & Johnson under the Tradename "Bandaid", has an outer layer or backing of a porous plastic film having an adhesive and a nonwoven pad attached to the films inner surface. When the bandage is applied to a patient the nonwoven pad is placed over a blister and comes into contact with the skin. The porous plastic film backing in the prior art is supposedly used to let moisture, that is trapped under the bandage, evaporate out through the pores in it. This is usually not the case, because although there are pores in the bandage, moisture trapped under the bandage against the skin does not evaporate out through them. This is quite evident in a visual observation of the skin after the bandage has been removed, because the skin is moist and wrinkled. This condition is mainly due to the fact that the pores in the plastic film only allow air to circulate in areas where the pores are. When moisture is trapped close to the skin it causes the skin to remain moist, thereby wrinkling the skin. If the skin remains moist, a blister or wound may be subjected to bacteria and a long healing time. In addition, this type of prior art bandage, if used as a protective covering to protect against blisters forming, will trap moisture, such as perspiration against the skin. This will keep the skin moist and make the skin subject to blisters. This is a condition that would not be tolerated by the wearer of this type bandage.
Another prior art bandage, is that such as described in U.S Pat. No. 3,247,845, wherein a bandage fabric, made from silk or cotton, is impregnated with a flexible collodion solution, which is then dried. When applying this bandage, the collodion solution must be redissolved in situ over the wound with an appropriate solvent. This type of bandage has many disadvantages. One such disadvantage is that it is only effective when used to cover a blister that has already formed. Another disadvantage is that a solvent must be used to activate the solution within the bandage, before the bandage becomes effective. Still another disadvantage is that this type of bandage requires a person to carry both a bandage and a solvent in their possession to properly use it.
In U.S. Pat. No. 4,296,499, there is described a foot covering article that is worn over the bare foot, underneath a sock, to prevent the formation of blisters. This prior art device is comprised of a single, porous, nonwoven sheet which is formed into a foot enveloping shape. There is a disadvantage associated with this article because it is obviously expensive to manufacture, and to purchase. It is, in essence, another sock to cover the foot.
The prior art has tried to achieve the aforementioned properties of air permeability, liquid barrier, flexibility, strength and a bacteria barrier in blister bandages, but has been unsuccessful. The present invention has achieved these properties by using a unique fabric structure that is superior to the prior art.